coverity#982591 Dereference after null check

Change-Id: I8651ecb0287d686da3e1ca6a6e46549abe3e0c38
Reviewed-on: https://gerrit.libreoffice.org/2225Reviewed-by: Andras Timar <atimar@suse.com>
Tested-by: Andras Timar <atimar@suse.com>

xmlsecurity/source/xmlsec/nss/securityenvironment_nssimpl.cxx

@@ -509,17 +509,20 @@ SecurityEnvironment_NssImpl::getPersonalCertificates() throw( SecurityException
         }
 
         priKeyList = PK11_ListPrivateKeysInSlot(slot) ;
-        if( priKeyList != NULL ) {
+        if( priKeyList != NULL )
+        {
             for( curPri = PRIVKEY_LIST_HEAD( priKeyList );
                 !PRIVKEY_LIST_END( curPri, priKeyList ) && curPri != NULL ;
-                curPri = PRIVKEY_LIST_NEXT( curPri ) ) {
+                curPri = PRIVKEY_LIST_NEXT( curPri ) )
+            {
                 xcert = NssPrivKeyToXCert( curPri->key ) ;
                 if( xcert != NULL )
                     certsList.push_back( xcert ) ;
             }
+            SECKEY_DestroyPrivateKeyList( priKeyList ) ;
         }
 
-        SECKEY_DestroyPrivateKeyList( priKeyList ) ;
+
     }
 
     //secondly, we try to find certificate from registered private keys.